Expert: Bruce E. Johnson - 2/17/2010

Question
Hi,

I have a few questions  I hope that's ok.  First, the 1st floor of our home is approximately 1550 Sq ft, as is the basement.  There are two steel support beams in the basement and they are about 8 feet apart.  On the first floor the flooring on either side of both beams is lower which is creating a "hump" for lack of a better word, that runs the length of these beams, rather than a level floor.  To me, it's very noticeable.  I'm a novice but the floor joices appear to be 2x8, possibly 2x10 and are doubled and sometime tripled, so each joice is fairly thick.  The beams as they meet the foundation appear to be level.  So is the house just settling around these beams, and is there anything I or anyone could to to level the floor?  Also, there is a section of the kitchen and family room floor that seems bouncy.  Is there any way to reinforce the floor from the basement to make it stronger?  Finally who best would be able to personally assess these and other structural questions I have and who best would be suited to fixing these problems.  I was thinking about a home inspector or structural engineer at least to assess, but then who could do this type of work......and more importantly do it the correct way?  Any advice would be greatly appreciated.
Thanks, Gary

Answer
Hi Gary, if your beams are 8' apart and your joists are 2x8 then I would say your beams are undersized.  A 2x8 joist should easily span 8' at 2-0 spacing. What you are describing is unusual unless I am missing something.  A hump at the beams would suggest that the joists are undersized.  Based on your information the joists do not appear to be undersized.  You can reinforce your joists by adding more joists along side them.  If your floor system doesn't have any bridging between them over the tops of the beams at least, then you may need to add some solid or x-braced bridging.  As far as consultation goes? I would go for the structural engineer..as far as doing the work? A structural contractor or general contractor with a good structural background should do it.  I hope this information helps, please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com